Fostamatinib Disodium

Oral presentation to feature updated data from the dose escalation and dose expansion phases of the ongoing Phase 1b study evaluating R289, Rigel's dual IRAK1/4 inhibitor, in patients with relapsed or refractory lower-risk MDS Three poster presentations will highlight data for TAVALISSE ® (fostamatinib disodium hexahydrate) in patients with chronic ITP and wAIHA SOUTH SAN FRANCISCO, Calif. , Nov. 4, 2026 /PRNewswire/ -- Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL), a commercial stage biotechnology company focused on hematologic disorders and cancer, today announced that data from the ongoing Phase 1b clinical study of R289 1 , a potent and selective inhibitor of interleukin receptor-associated kinases 1 and 4 (IRAK1/4), in patients with lower-risk myelodysplastic syndrome (MDS) who are relapsed or refractory (R/R) to prior therapies will be presented in an oral session at the 68 th American Society of Hematology (ASH) Annual Meeting and Exposition on Saturday, December 12, 2026. In addition, the ASH Annual Meeting will feature three poster presentations for TAVALISSE ® (fostamatinib disodium hexahydrate) in patients with immune thrombocytopenia (ITP) and warm autoimmune hemolytic anemia (wAIHA). The ASH Annual Meeting is taking place from December 12-15, 2026, in New Orleans, Louisiana and virtually. "Data from the dose escalation phase of the ongoing Phase 1b study of R289 in patients with relapsed or refractory lower-risk MDS was presented at an oral session at last year's ASH," said Alison L. Hannah, M.D., Rigel's chief medical officer. "This year the data from our randomized dose expansion phase will also be presented at an oral session, providing an update on both efficacy, including the reduction of transfusion dependence, and safety. We continue to be encouraged by our evolving data in this heavily pretreated patient population." Key highlights from the ASH abstracts include: In the ongoing Phase 1b study of R289 in patients with R/R lower-risk MDS, there were 64 patients enrolled as of July 16, 2026, including 33 patients in the dose escalation phase and 31 patients in the dose expansion phase. At the data cut off, R289 continues to be generally well tolerated in this elderly, heavily pretreated lower-risk MDS patient population, the majority of whom were considered to have high transfusion burden (HTB) disease at baseline. Updated study data as of a planned mid-November data cut will be presented in the oral session, including preliminary efficacy data from the dose expansion phase of the study. In a retrospective real-world analysis of 90 patients with ITP receiving fostamatinib plus a thrombopoietin receptor agonist (TPO-RA), combination treatment was associated with increased platelet counts. Among 38 patients with available measurements during months 7-12, 81.6% had platelet counts ≥50 × 10³/µL, an increase from 33.3% of 90 patients at baseline. These findings support a treatment approach targeting multiple mechanisms of disease through the combination of fostamatinib and TPO-RAs. Data from an interim analysis investigating fostamatinib in 799 patients enrolled in the ongoing post-marketing surveillance in Japan will be presented. No new safety signals were detected. Platelet counts increased within two weeks of fostamatinib initiation, with responses maintained at 12 months in a subset of patients who continued treatment and had available follow-up data. In an open-label long-term extension study enrolling 71 patients with wAIHA that were treated with fostamatinib, durable hemoglobin responses were observed in >50% of patients during follow-up through Week 104. The long-term safety pro consistent with the established safety pro fostamatinib, with no new safety signals identified. Fostamatinib remains investigational in this setting. ASH Annual Meeting abstracts may be accessed online at . Abstract Title Lead Author / Presenter Presentation Type / Publication # Session Title Session Date / Time (CT) R289 Dose Escalating / Dose Expansion Study of R289, a Dual IRAK 1/4 Inhibitor, in Patients with Relapsed/Refractory (R/R) Lower Risk Myelodysplastic Syndrome (LR-MDS) Guillermo Garcia-Manero, MD Oral presentation Publication #251 637. Myelodysplastic Syndromes: Clinical and Epidemiological: Novel Therapeutic Strategies and Prognostic Stratification in MDS and MDS/MPN Saturday, December 12, 2026 3:00pm – 3:15pm TAVALISSE (fostamatinib disodium hexahydrate) Platelet Responses with Combination Therapy of Fostamatinib and Thrombopoietin Receptor Agonists in Immune Thrombocytopenia: An Updated Real-World Analysis David J. Kuter, MD, DPhil Poster presentation Publication #1250 311. Disorders of Platelet Number or Function: Clinical and Epidemiological: Poster I Saturday, December 12, 2026 5:30pm – 7:30pm Real-world safety, effectiveness, and predictors of responses to fostamatinib in patients with ITP: interim analysis of a nationwide post-marketing surveillance in Japan Masataka Kuwana, MD Poster presentation Publication #1252 311. Disorders of Platelet Number or Function: Clinical and Epidemiological: Poster I Saturday, December 12, 2026 5:30pm – 7:30pm Hemoglobin Responses With Fostamatinib in a Long-Term Extension Trial in Warm Autoimmune Hemolytic Anemia David J. Kuter, MD, DPhil Poster presentation Publication #4619 101. Red Cells and Erythropoiesis, Excluding Iron: Poster III Monday, December 14, 2026 6:00pm – 8:00pm REZLIDHIA (olutasidenib) Efficacy of Olutasidenib After Venetoclax in IDH1-Mutated Relapsed/Refractory Acute Myeloid Leukemia: A Systematic Literature Review and Meta-Analysis Jorge E. Cortes, MD Publication only #7191 N/A N/A About R289 R289 is a prodrug of R835, an IRAK1/4 dual inhibitor, which has been shown in preclinical studies to block inflammatory cytokine production in response to toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) family signaling. TLRs and IL-1Rs play a critical role in the innate immune response and dysregulation of these pathways can lead to various inflammatory conditions. Chronic stimulation of both these receptor systems is thought to cause the pro-inflammatory environment in the bone marrow responsible for persistent cytopenias in lower-risk MDS patients. 2 About ITP In patients with immune thrombocytopenia (ITP), the immune system attacks and destroys the body's own blood platelets, which play an active role in blood clotting and healing. Common symptoms of ITP are excessive bruising and bleeding. Patients suffering with chronic ITP may live with an increased risk of severe bleeding events that can result in serious medical complications or even death. Current therapies for ITP include steroids, blood platelet production boosters (TPO-RAs), and splenectomy. However, not all patients respond to existing therapies. As a result, there remains a significant medical need for additional treatment options for patients with ITP. About AML Acute myeloid leukemia (AML) is a rapidly progressing cancer of the blood and bone marrow that affects myeloid cells, which normally develop into various types of mature blood cells. AML occurs primarily in adults and accounts for about 1 percent of all adult cancers. The American Cancer Society estimates that there will be about 22,720 new cases in the United States, most in adults, in 2026. 3 Relapsed AML affects about half of all patients who, following treatment and remission, experience a return of leukemia cells in the bone marrow. 4,5 Refractory AML, which affects between 10 and 40 percent of newly diagnosed patients, occurs when a patient fails to achieve remission even after intensive treatment. 6 Quality of life declines for patients with each successive line of treatment for AML, and well-tolerated treatments in relapsed or refractory disease remain an unmet need. About TAVALISSE ® Indication TAVALISSE (fostamatinib disodium hexahydrate) is indicated for the treatment of thrombocytopenia in adult patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment. Important Safety Information Warnings and Precautions Hypertension can occur with TAVALISSE treatment. Patients with pre-existing hypertension may be more susceptible to the hypertensive effects. Monitor blood pressure every 2 weeks until stable, then monthly, and adjust or initiate antihypertensive therapy for blood pressure control maintenance during therapy. If increased blood pressure persists, TAVALISSE interruption, reduction, or discontinuation may be required. Elevated liver function tests (LFTs), mainly ALT and AST, can occur with TAVALISSE. Monitor LFTs monthly during treatment. If ALT or AST increase to ≥3 x upper limit of normal, manage hepatotoxicity using TAVALISSE interruption, reduction, or discontinuation. Diarrhea occurred in 31% of patients and severe diarrhea occurred in 1% of patients treated with TAVALISSE. Monitor patients for the development of diarrhea and manage using supportive care measures early after the onset of symptoms. If diarrhea becomes severe (≥Grade 3), interrupt, reduce dose or discontinue TAVALISSE. Neutropenia occurred in 6% of patients treated with TAVALISSE; febrile neutropenia occurred in 1% of patients. Monitor the ANC monthly and for infection during treatment. Manage toxicity with TAVALISSE interruption, reduction, or discontinuation. TAVALISSE can cause fetal harm when administered to pregnant women. Advise pregnant women the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment and for at least 1 month after the last dose. Verify pregnancy status prior to initiating TAVALISSE. It is unknown if TAVALISSE or its metabolite is present in human milk. Because of the potential for serious adverse reactions in a breastfed child, advise a lactating woman not to breastfeed during TAVALISSE treatment and for at least 1 month after the last dose. Drug Interactions Concomitant use of TAVALISSE with strong CYP3A4 inhibitors increases exposure to the major active metabolite of TAVALISSE (R406), which may increase the risk of adverse reactions. Monitor for toxicities that may require a reduction in TAVALISSE dose. It is not recommended to use TAVALISSE with strong CYP3A4 inducers, as concomitant use reduces exposure to R406. Concomitant use of TAVALISSE may increase concentrations of some CYP3A4 substrate drugs and may require a dose reduction of the CYP3A4 substrate drug. Concomitant use of TAVALISSE may increase concentrations of BCRP substrate drugs (eg, rosuvastatin) and P-Glycoprotein (P-gp) substrate drugs (eg, digoxin), which may require a dose reduction of the BCRP and P-gp substrate drug. Adverse Reactions Serious adverse drug reactions in the ITP double-blind studies were febrile neutropenia, diarrhea, pneumonia, and hypertensive crisis, which occurred in 1% of TAVALISSE patients. In addition, severe adverse reactions occurred including dyspnea and hypertension (both 2%), neutropenia, arthralgia, chest pain, diarrhea, dizziness, nephrolithiasis, pain in extremity, toothache, syncope, and hypoxia (all 1%). Common adverse reactions (≥5% and more common than placebo) from FIT-1 and FIT-2 included: diarrhea, hypertension, nausea, dizziness, ALT and AST increased, respiratory infection, rash, abdominal pain, fatigue, chest pain, and neutropenia. Click here for Important Safety Information and Full Prescribing Information . About REZLIDHIA ® INDICATION REZLIDHIA is indicated for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with a susceptible isocitrate dehydrogenase-1 (IDH1) mutation as detected by an FDA-approved test. IMPORTANT SAFETY INFORMATION WARNING: DIFFERENTIATION SYNDROME Differentiation syndrome, which can be fatal, can occur with REZLIDHIA treatment. Symptoms may include dyspnea, pulmonary infiltrates/pleuropericardial effusion, kidney injury, hypotension, fever, and weight gain. If differentiation syndrome is suspected, withhold REZLIDHIA and initiate treatment with corticosteroids and hemodynamic monitoring until symptom resolution. WARNINGS AND PRECAUTIONS Differentiation Syndrome REZLIDHIA can cause differentiation syndrome. In the clinical trial of REZLIDHIA in patients with relapsed or refractory AML, differentiation syndrome occurred in 16% of patients, with grade 3 or 4 differentiation syndrome occurring in 8% of patients treated, and fatalities in 1% of patients. Differentiation syndrome is associated with rapid proliferation and differentiation of myeloid cells and may be life-threatening or fatal. Symptoms of differentiation syndrome in patients treated with REZLIDHIA included leukocytosis, dyspnea, pulmonary infiltrates/pleuropericardial effusion, kidney injury, fever, edema, pyrexia, and weight gain. Of the 25 patients who experienced differentiation syndrome, 19 (76%) recovered after treatment or after dose interruption of REZLIDHIA. Differentiation syndrome occurred as early as 1 day and up to 18 months after REZLIDHIA initiation and has been observed with or without concomitant leukocytosis. If differentiation syndrome is suspected, temporarily withhold REZLIDHIA and initiate systemic corticosteroids (e.g., dexamethasone 10 mg IV every 12 hours) for a minimum of 3 days and until resolution of signs and symptoms. If concomitant leukocytosis is observed, initiate treatment with hydroxyurea, as clinically indicated. Taper corticosteroids and hydroxyurea after resolution of symptoms. Differentiation syndrome may recur with premature discontinuation of corticosteroids and/or hydroxyurea treatment. Institute supportive measures and hemodynamic monitoring until improvement; withhold dose of REZLIDHIA and consider dose reduction based on recurrence. Hepatotoxicity REZLIDHIA can cause hepatotoxicity, presenting as increased alanine aminotransferase (ALT), increased aspartate aminotransferase (AST), increased blood alkaline phosphatase, and/or elevated bilirubin. Of 153 patients with relapsed or refractory AML who received REZLIDHIA, hepatotoxicity occurred in 23% of patients; 13% experienced grade 3 or 4 hepatotoxicity. One patient treated with REZLIDHIA in combination with azacitidine in the clinical trial, a combination for which REZLIDHIA is not indicated, died from complications of drug-induced liver injury. The median time to onset of hepatotoxicity in patients with relapsed or refractory AML treated with REZLIDHIA was 1.2 months (range: 1 day to 17.5 months) after REZLIDHIA initiation, and the median time to resolution was 12 days (range: 1 day to 17 months). The most common hepatotoxicities were elevations of ALT, AST, blood alkaline phosphatase, and blood bilirubin. Monitor patients frequently for clinical symptoms of hepatic dysfunction such as fatigue, anorexia, right upper abdominal discomfort, dark urine, or jaundice. Obtain baseline liver function tests prior to initiation of REZLIDHIA, at least once weekly for the first two months, once every other week for the third month, once in the fourth month, and once every other month for the duration of therapy. If hepatic dysfunction occurs, withhold, reduce, or permanently discontinue REZLIDHIA based on recurrence/severity. ADVERSE REACTIONS The most common (≥20%) adverse reactions, including laboratory abnormalities, were aspartate aminotransferase increased, alanine aminotransferase increased, potassium decreased, sodium decreased, alkaline phosphatase increased, nausea, creatinine increased, fatigue/malaise, arthralgia, constipation, lymphocytes increased, bilirubin increased, leukocytosis, uric acid increased, dyspnea, pyrexia, rash, lipase increased, mucositis, diarrhea and transaminitis. DRUG INTERACTIONS Avoid concomitant use of REZLIDHIA with strong or moderate CYP3A inducers. Avoid concomitant use of REZLIDHIA with sensitive CYP3A substrates unless otherwise instructed in the substrates prescribing information. If concomitant use is unavoidable, monitor patients for loss of therapeutic effect of these drugs. LACTATION Advise women not to breastfeed during treatment with REZLIDHIA and for 2 weeks after the last dose. GERIATRIC USE No overall differences in effectiveness were observed between patients 65 years and older and younger patients. Compared to patients younger than 65 years of age, an increase in incidence of hepatotoxicity and hypertension was observed in patients ≥65 years of age. HEPATIC IMPAIRMENT In patients with mild or moderate hepatic impairment, closely monitor for increased probability of differentiation syndrome. Click here for Important Safety Information and Full Prescribing Information , including Boxed WARNING. To report side effects of prescription drugs to the FDA, visit or call 1-800-FDA-1088 (800-332-1088). TAVALISSE and REZLIDHIA are registered trademarks of Rigel Pharmaceuticals, Inc. About Rigel Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL) is a biotechnology company dedicated to discovering, developing and providing novel therapies that significantly improve the lives of patients with hematologic disorders and cancer. Founded in 1996, Rigel is based in South San Francisco, California. For more information on Rigel, the Company's marketed products and pipeline of potential products, visit . R289 is an investigational compound not approved by the FDA. Sallman DA et al. Unraveling the Pathogenesis of MDS: The NLRP3 Inflammasome and Pyroptosis Drive the MDS Phenotype . Front Oncol. June 16, 2016. doi: The American Cancer Society. Key Statistics for Acute Myeloid Leukemia (AML). Revised January 13, 2026. Accessed October 30, 2026: Patel, A, et al. Outcomes of Patients With Acute Myeloid Leukemia Who Relapse After 5 Years of Complete Remission . 2021 Sep 7;28(7):811-814. doi: Thol F, Ganser, A. Treatment of Relapsed Acute Myeloid Leukemia . Curr. Treat. Options on Oncol. (2020) 21: 66. doi: Thol F, Schlenk RF, Heuser M, Ganser A. How I treat refractory and early relapsed acute myeloid leukemia . Blood (2015) 126 (3): 319-27. doi: Forward Looking Statements This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 relating to, among other things, the anticipated timing and content of presentations at the 2026 American Society of Hematology Annual Meeting and Exposition; the planned data cutoff and availability of updated data from the ongoing Phase 1b study of R289; the progress and potential outcomes of the dose escalation and dose expansion phases of that study; the potential safety, tolerability and efficacy of R289, including its potential to reduce transfusion dependence in patients with lower-risk myelodysplastic syndrome; and the potential therapeutic benefits and clinical utility of fostamatinib in the patient populations and treatment settings described in this release. Any statements contained in this press release that are not statements of historical fact may be deemed to be forward-looking statements. Words such as "anticipates," "believes," "expects," "intends," "may," "plans," "potential," "will" and similar expressions are intended to identify such forward-looking statements. Forward-looking statements are neither historical facts nor assurances of future performance. They are based on Rigel's current beliefs, expectations and assumptions and involve significant risks and uncertainties that are difficult to predict and, in many cases, are beyond Rigel's control. Actual results and the timing of events could differ materially from those expressed or implied by these forward-looking statements as a result of various risks and uncertainties, including, without limitation, risks that clinical studies, data collection, analyses or presentations may be delayed or may not proceed as anticipated; risks that preliminary, interim or limited clinical data may not be predictive of final results, results in larger patient populations or results in subsequent clinical trials; limitations of retrospective, observational, uncontrolled and subgroup analyses, including potential selection bias, confounding factors and incomplete follow-up; risks that clinical trial results may not be predictive of real-world outcomes; risks that additional data, analyses or experience may alter assessments of the safety, tolerability, efficacy or therapeutic potential of R289 or fostamatinib; risks that R289 or fostamatinib may have unintended side effects or adverse reactions; risks that clinical results or decisions by regulatory authorities may not support further development or approval for investigational uses; risks associated with reliance on third parties for clinical development, manufacturing, supply and other services; the availability and allocation of financial, personnel and other resources to fund Rigel's development programs; competition from other therapies; and other risks described in the "Risk Factors" section of Rigel's Quarterly Report on Form 10-Q for the quarter ended June 30, 2026 and subsequent filings with the Securities and Exchange Commission. Any forward-looking statement in this press release speaks only as of the date on which it is made. Rigel undertakes no obligation to update or revise any forward-looking statements, whether as a result of new information, future developments or otherwise, except as required by law. Contact for Investors & Media: Investors: Rigel Pharmaceuticals, Inc. 650.624.1232 ir@rigel.com Media: David Rosen Argot Partners 646.461.6387 david.rosen@argotpartners.com View original content to download multimedia: SOURCE Rigel Pharmaceuticals, Inc.

Second quarter 2026 total revenues of $78.7 million, including net product sales of $67.0 million and contract revenues from collaborations of $11.7 million, and net income of $17.3 million Expanded commercial portfolio with the in-license of VEPPANU™ (vepdegestrant), with U.S. commercial availability expected in mid-August Advanced R289 development program; Phase 1b study in patients with lower-risk MDS remains on track to complete enrollment in the dose expansion portion and select the recommended Phase 2 dose in the second half of 2026 Updated 2026 Outlook: Total revenues of approximately $285 to $295 million, which includes net product sales, excluding VEPPANU, of $255 to $265 million and contract revenues from collaborations of approximately $30 million Conference call and webcast scheduled today at 4:30 p.m. Eastern Time SOUTH SAN FRANCISCO, Calif., Aug. 4, 2026 /PRNewswire/ -- Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL), a commercial stage biotechnology company focused on hematologic disorders and cancer, today reported financial results for the second quarter ended June 30, 2026, including sales of TAVALISSE® (fostamatinib disodium hexahydrate), GAVRETO® (pralsetinib) and REZLIDHIA® (olutasidenib), and recent business progress, including the in-license of VEPPANU™ (vepdegestrant), a PRoteolysis TArgeting Chimera (PROTAC). "Rigel delivered a strong second quarter, highlighted by record net product sales, continued profitability and the in-license of VEPPANU, the first and only FDA-approved PROTAC for patients with ER+/HER2-, ESR1-mutated advanced or metastatic breast cancer. We expect VEPPANU to be commercially available later this month, further expanding our commercial business in hematology and oncology," said Raul Rodriguez, Rigel's president and CEO. "We are also advancing the development of R289 in our ongoing Phase 1b study in patients with R/R lower-risk MDS, and remain on track to complete enrollment in the dose expansion phase of the study, select a recommended Phase 2 dose in the second half of 2026 and share preliminary data by year end." Second Quarter 2026 Business Update Corporate Rigel entered into an exclusive, global licensing agreement with Arvinas, Inc. (Arvinas) and Pfizer Inc. (Pfizer) to develop, manufacture and commercialize VEPPANU (vepdegestrant). VEPPANU is the first and only PROTAC approved by the U.S. Food and Drug Administration (FDA) for the treatment of adults with estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-), estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer (mBC), as detected by an FDA-authorized test, with disease progression following at least one line of endocrine therapy. The agreement became effective on June 11, 2026, and Rigel paid the upfront payment of $70.0 million to Arvinas and Pfizer in the second quarter. Upon close of the transaction, Rigel immediately initiated launch activities and expects VEPPANU to be commercially available in the United States for the treatment of second line-plus (2L+) ER+/HER2-, ESR1-mutated mBC in mid-August 2026. In July, Rigel announced the appointment of Alison L. Hannah, M.D. to the role of Executive Vice President and Chief Medical Officer. Dr. Hannah has decades of oncology drug development experience and served on Rigel's Board of Directors since 2021. She resigned from Rigel's Board of Directors in connection with her appointment. Commercial Second quarter net product sales were $67.0 million, an increase of 14% from the same period of 2025. Rigel's partner Knight Therapeutics Inc. (Knight) received regulatory approval from Brazil's Agência Nacional de Vigilância Sanitária (ANVISA) in May for TAVALISSE for the treatment of adult patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment. Also in May, Knight commercially launched TAVALISSE in Mexico. Rigel's partner Kissei Pharmaceutical Co., Ltd. (Kissei) submitted a new drug application for manufacturing and marketing approval in Japan for olutasidenib in May. In connection with the submission, Rigel received a $4.0 million regulatory milestone payment from Kissei during the second quarter. Clinical Development Rigel continues to advance its Phase 1b clinical study of R2891, a potent and selective dual inhibitor of interleukin receptor-associated kinases 1 and 4 (IRAK1/4), in patients with relapsed or refractory (R/R) lower-risk myelodysplastic syndrome (MDS), with enrollment in the dose expansion phase ongoing and on track to be completed in the second half of 2026. The company expects to select the recommended Phase 2 dose in the second half of 2026 and share preliminary dose expansion data by year end. The 2026 American Society of Clinical Oncology (ASCO) Annual Meeting and European Hematology Association (EHA) 2026 Congress featured an oral presentation and several poster presentations for pralsetinib and olutasidenib. The final data from the Phase 3 AcceleRET-Lung clinical trial of pralsetinib as first-line treatment of rearranged during transfection (RET) fusion-positive non-small cell lung cancer (NSCLC) were presented in an oral session at ASCO. In addition, ASCO and EHA featured poster presentations that included additional data for pralsetinib and data for olutasidenib for the treatment of R/R isocitrate dehydrogenase-1 (IDH1)-mutated acute myeloid leukemia (AML). Key Publication A paper titled "Preclinical Characterization and Early Development of R835, a Novel, Selective Dual IRAK1 and IRAK4 Inhibitor," was published in Scientific Reports in July. R835, the active metabolite of the prodrug R289, potently and selectively inhibited toll-like receptor (TLR) and interleukin-1 receptor (IL-1R)-dependent proinflammatory cytokine production in multiple preclinical models, demonstrating efficacy in both prophylactic and treatment preclinical settings. Additionally, in a placebo-controlled, double-blind, Phase 1, first-in-human study in 82 healthy participants, R835 was well tolerated with a favorable pharmacokinetic profile across all dose levels evaluated, and markedly inhibited lipopolysaccharide (LPS)-induced peak cytokine concentrations by approximately 40-80% compared to placebo. These data provided clinical proof of mechanism of a dual IRAK1/4 inhibitor suppressing proinflammatory cytokine release in humans. Second Quarter and Year-to-Date 2026 Financial Update For the second quarter ended June 30, 2026, total revenues were $78.7 million, consisting of $67.0 million in net product sales and $11.7 million in contract revenues from collaborations. Net product sales increased 14% compared to $58.9 million in the same period of 2025. TAVALISSE net product sales were $47.4 million, an increase of 18% compared to $40.1 million in the same period of 2025. GAVRETO net product sales were $10.7 million, a decrease of 10% compared to $11.8 million in the same period of 2025. REZLIDHIA net product sales were $8.9 million, an increase of 27% compared to $7.0 million in the same period of 2025. Contract revenues from collaborations primarily consisted of $5.8 million of revenue from Kissei, which included a $4.0 million regulatory milestone payment in connection with the marketing authorization application submission for olutasidenib in Japan and delivery of drug supplies; $5.0 million of revenue from Grifols S.A. (Grifols) related to earned royalties and delivery of drug supplies; and $0.3 million of revenue from Medison Pharma (Medison) related to earned royalties and delivery of drug supplies. Contract revenues from collaborations in the prior year period included $40.0 million in non-cash revenue resulting from the release of the remaining cost share liability from Rigel's collaboration agreement with Eli Lilly and Company (Lilly). Total costs and expenses were $55.1 million, compared to $40.6 million for the same period of 2025. The increase in costs and expenses was primarily driven by higher personnel-related costs, cost of product sales, and research and development costs, including the continued progress of the R289 program and costs associated with development activities under Rigel's license agreement with Arvinas and Pfizer. Income before income taxes was $23.6 million, compared to $60.0 million for the same period of 2025. Rigel reported net income of $17.3 million, or $0.93 basic and $0.88 diluted per share, compared to $59.6 million, or $3.33 basic and $3.28 diluted per share, for the same period of 2025. As noted above, the prior year period included $40.0 million in non-cash revenue related to Rigel's collaboration agreement with Lilly. For the six months ended June 30, 2026, total revenues were $137.5 million, consisting of $121.9 million in net product sales and $15.6 million in contract revenues from collaborations. Net product sales increased 19% compared to $102.5 million in the same period of 2025. TAVALISSE net product sales were $84.7 million, an increase of 24% compared to $68.5 million in the same period of 2025. GAVRETO net product sales were $20.3 million, a decrease of 2% compared to $20.8 million in the same period of 2025. REZLIDHIA net product sales were $17.0 million, an increase of 29% compared to $13.1 million in the same period of 2025. Contract revenues from collaborations primarily consisted of $7.6 million of revenue from Kissei, including a $4.0 million regulatory milestone and delivery of drug supplies; $6.8 million of revenue from Grifols related to earned royalties and delivery of drug supplies; and $0.5 million of revenue from Medison related to earned royalties and delivery of drug supplies. Contract revenues from collaborations in the prior year period included $40.0 million in non-cash revenue resulting from the release of the remaining cost share liability from Rigel's collaboration agreement with Lilly and a $3.0 million regulatory milestone in connection with the approval of TAVALISSE in the Republic of Korea. Total costs and expenses were $102.1 million, compared to $81.1 million for the same period of 2025. The increase in costs and expenses was primarily driven by higher personnel-related costs; research and development costs, including the continued progress of the R289 program and costs associated with development activities under Rigel's license agreement with Arvinas and Pfizer; cost of product sales, and commercial-related expenses. Income before income taxes was $35.2 million, compared to $71.5 million for the same period of 2025. Rigel reported net income of $25.9 million, or $1.40 basic and $1.32 diluted per share, compared to $71.1 million, or $3.98 basic and $3.91 diluted per share, for the same period of 2025. As noted above, the prior year period included $40.0 million in non-cash revenue related to Rigel's collaboration agreement with Lilly. Cash, cash equivalents and short-term investments as of June 30, 2026 was $95.3 million, compared to $155.0 million as of December 31, 2025. 2026 Outlook Rigel has increased its 2026 total revenues guidance to approximately $285 to $295 million, from the prior range of approximately $275 to $290 million, which includes: Net product sales of approximately $255 to $265 million. Contract revenues of approximately $30 million, an increase from the prior range of approximately $20 to $25 million. The above revenue guidance excludes VEPPANU. The company also continues to anticipate it will report positive net income for the full year 2026, while funding existing and new clinical development programs. Conference Call and Webcast with Slides Today at 4:30 p.m. Eastern Time Rigel will hold a live conference call and webcast today at 4:30 p.m. Eastern Time (1:30 p.m. Pacific Time). Participants can access the live conference call by dialing (877) 407-3088 (domestic) or (201) 389-0927 (international). The conference call will also be webcast live and will be accessible from the Investor Relations section of the company's website at . The webcast will be archived and available for replay after the call via the Rigel website. About ITP In patients with immune thrombocytopenia (ITP), the immune system attacks and destroys the body's own blood platelets, which play an active role in blood clotting and healing. Common symptoms of ITP are excessive bruising and bleeding. Patients suffering with chronic ITP may live with an increased risk of severe bleeding events that can result in serious medical complications or even death. Current therapies for ITP include steroids, blood platelet production boosters (TPO-RAs), and splenectomy. However, not all patients respond to existing therapies. As a result, there remains a significant medical need for additional treatment options for patients with ITP. About NSCLC It is estimated that over 229,000 adults in the U.S. will be diagnosed with lung cancer in 2026. Lung cancer is the leading cause of cancer death in the U.S., with non-small cell lung cancer (NSCLC) being the most common type accounting for 77% of all lung cancer diagnoses.2 RET fusions are implicated in approximately 1-2% of patients with NSCLC.3 About AML Acute myeloid leukemia (AML) is a rapidly progressing cancer of the blood and bone marrow that affects myeloid cells, which normally develop into various types of mature blood cells. AML occurs primarily in adults and accounts for about 1 percent of all adult cancers. The American Cancer Society estimates that there will be about 22,720 new cases in the United States, most in adults, in 2026.4 Relapsed AML affects about half of all patients who, following treatment and remission, experience a return of leukemia cells in the bone marrow. 5,6 Refractory AML, which affects between 10 and 40 percent of newly diagnosed patients, occurs when a patient fails to achieve remission even after intensive treatment.7 Quality of life declines for patients with each successive line of treatment for AML, and well-tolerated treatments in relapsed or refractory disease remain an unmet need. About ER+/HER2-, ESR1 -mutated Metastatic Breast Cancer Breast cancer is the most common cancer in women in the United States, except for skin cancers.8 The estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER+/HER2-) patient population represents the majority (70%) of breast cancer, where treatment with endocrine therapies (aromatase inhibitors) is the standard of care. While endocrine therapy remains a cornerstone of metastatic ER+/HER2- breast cancer treatment, up to 50% of patients treated with endocrine therapy and a CDK4/6 inhibitor acquire estrogen receptor 1 gene (ESR1) mutations, resulting in endocrine resistance and poor prognosis. Treatment options in second-line and later ER+/HER2-, ESR1-mutated advanced or metastatic breast cancer setting include chemotherapy, selective estrogen receptor degraders (SERDs), and as of May 2026, vepdegestrant, the first and only FDA-approved oral PROteolysis TArgeting Chimera (PROTAC). About TAVALISSE ® TAVALISSE (fostamatinib disodium hexahydrate) is indicated for the treatment of thrombocytopenia in adult patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment. Please click here for Important Safety Information and Full Prescribing Information for TAVALISSE. About GAVRETO ® GAVRETO is indicated for the treatment of adult patients with metastatic rearranged during transfection (RET) fusion-positive non-small cell lung cancer (NSCLC) as detected by an FDA-approved test and adult and pediatric patients 12 years of age and older with advanced or metastatic RET fusion-positive thyroid cancer who require systemic therapy and who are radioactive iodine-refractory (if radioactive iodine is appropriate).* *Thyroid indication is approved under accelerated approval based on overall response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trial(s). Please click here for Important Safety Information and Full Prescribing Information, including Boxed WARNING, for GAVRETO. About REZLIDHIA ® REZLIDHIA is indicated for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with a susceptible isocitrate dehydrogenase-1 (IDH1) mutation as detected by an FDA-approved test. Please click here for Important Safety Information and Full Prescribing Information, including Boxed WARNING, for REZLIDHIA. About VEPPANU™ VEPPANU is indicated for the treatment of adults with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, estrogen receptor-1 (ESR1)-mutated advanced or metastatic breast cancer, as detected by an FDA-authorized test, with disease progression following at least one line of endocrine therapy. Please click here for Important Safety Information and Full Prescribing Information for VEPPANU. To report side effects of prescription drugs to the FDA, visit or call 1-800-FDA-1088 (800-332-1088). TAVALISSE, GAVRETO and REZLIDHIA are registered trademarks and VEPPANU is a trademark of Rigel Pharmaceuticals, Inc. About Rigel Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL) is a biotechnology company dedicated to discovering, developing and providing novel therapies that significantly improve the lives of patients with hematologic disorders and cancer. Founded in 1996, Rigel is based in South San Francisco, California. For more information on Rigel, the Company's marketed products and pipeline of potential products, visit . R289 is an investigational compound not approved by the FDA. The American Cancer Society. Key Statistics for Lung Cancer. Revised January 13, 2026. Accessed June 30, 2026: Kato, S. et al. RET Aberrations in Diverse Cancers: Next-Generation Sequencing of 4,871 Patients. Clin Cancer Res. 2017;23(8):1988-1997 doi: 10.1158/1078-0432.CCR-16-1679 The American Cancer Society. Key Statistics for Acute Myeloid Leukemia (AML). Revised January 13, 2026. Accessed June 30, 2026: Patel, A, et al. Outcomes of Patients With Acute Myeloid Leukemia Who Relapse After 5 Years of Complete Remission. 2021 Sep 7;28(7):811-814. doi: Thol F, Ganser, A. Treatment of Relapsed Acute Myeloid Leukemia. Curr. Treat. Options on Oncol. (2020) 21: 66. doi: Thol F, Schlenk RF, Heuser M, Ganser A. How I treat refractory and early relapsed acute myeloid leukemia. Blood (2015) 126 (3): 319-27. doi: The American Cancer Society. Key Statistics for Breast Cancer. Revised June 24, 2026. Accessed June 30, 2026: Forward Looking Statements This press release contains forward-looking statements relating to, among other things, expected commercial launches and commercial availability, commercial, financial and clinical results, projections of financial performance and outlook for 2026, expectations for growing our commercial business and successfully executing our commercial strategy, continued enrollment of our R289 study, presentation of study data, expectation of clinical outcomes, continued ability to develop and commercialize VEPPANU, TAVALISSE, GAVRETO, REZLIDHIA, and R289 domestically and in certain international markets, the Company's ability to fund its existing and future clinical development programs, and expectations for our partnering, licensing, commercialization and collaboration efforts. Any statements contained in this press release that are not statements of historical fact may be deemed to be forward-looking statements. Forward-looking statements can be identified by words such as "anticipates", "plan", "outlook", "potential", "may", "look to", "expects", "will", "initial", "promising", and similar expressions in reference to future periods. Forward-looking statements are neither historical facts nor assurances of future performance. Instead, they are based on Rigel's current beliefs, expectations, and assumptions and hence they inherently involve significant risks, uncertainties and changes in circumstances that are difficult to predict and many of which are outside of our control. Therefore, you should not rely on any of these forward-looking statements. These forward-looking statements include, without limitation, anticipated financial performance and profitability for 2026; expected product sales and commercial growth; the anticipated timing, progress and results of clinical development activities for R289, including enrollment, dose selection and data readouts; the Company's ability to fund its existing and future development programs; the anticipated commercial launch and commercialization of VEPPANU; the Company's ability to execute its commercial strategy and its partnering, licensing, commercialization, collaboration and potential business development activities. Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties, which include, without limitation, risks and uncertainties associated with the commercialization and marketing of VEPPANU, TAVALISSE, GAVRETO and REZLIDHIA, including uncertainties relating to physician adoption, patient demand, market acceptance, reimbursement and pricing; risks that the FDA, European Medicines Agency, PMDA or other regulatory authorities may make adverse decisions regarding VEPPANU, TAVALISSE, GAVRETO, REZLIDHIA or R289; operational, regulatory or other risks that can affect the timing of enrollment and data availability for R289 clinical development; risks that clinical trials may not be predictive of real-world results or of results in subsequent clinical trials; risks that VEPPANU, TAVALISSE, GAVRETO, REZLIDHIA or R289 may have unintended side effects, adverse reactions or incidents of misuse; the availability of resources to develop or market Rigel's product candidates; market competition; product demand variability; pricing/reimbursement dynamics; unanticipated business needs and other developments, including potential partnering, licensing or other collaboration arrangements, which could impact Rigel's funding needs or other internal resource demands, as well as other risks detailed from time to time in Rigel's reports filed with the Securities and Exchange Commission, including its Quarterly Report on Form 10-Q for the quarter ended March 31, 2026 and subsequent filings. Any forward-looking statement made by us in this press release is based only on information currently available to us and speaks only as of the date on which it is made. Rigel does not undertake any obligation to update forward-looking statements, whether written or oral, that may be made from time to time, whether as a result of new information, future developments or otherwise, and expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein, except as required by law. Contact for Investors & Media: Investors: Rigel Pharmaceuticals, Inc. 650.624.1232 [email protected] Media: David Rosen Argot Partners 646.461.6387 [email protected] SOURCE Rigel Pharmaceuticals, Inc. 21% more press release views with Request a Demo